I personally think this model of phone is the most beautiful of all phones ever made. It is a Western
Electric Model 201. This unit is from my own collection.
The base is a D2 and the handset is an E1. This is only half of the phone. The other half is in the ringer box. That's where the induction coil and capacitor (network) and bells reside.
This was the successor to the candlestick. The E1 handset was the first to use the novel concept of having both the transmitter and the receiver in one piece. It's transmitter was so successful it was carried forward into the F1 handset years later.
This phone has a round base. A later style that looked very similar had an oval base and was usually equipped with the newer F1 handet.